1 files changed, 41 insertions, 2 deletions
diff --git a/src/saml2/cryptography/pki.py b/src/saml2/cryptography/pki.py
index 8c59fdaf..0aa6d2b8 100644
--- a/src/saml2/cryptography/pki.py
+++ b/src/saml2/cryptography/pki.py
@@ -1,9 +1,48 @@
 """This module provides methods for PKI operations."""
 
-import cryptography.hazmat.backends as _backends
+from logging import getLogger as get_logger
+
 import cryptography.x509 as _x509
+from cryptography.hazmat.primitives.serialization import Encoding as _cryptography_encoding
+
+
+logger = get_logger(__name__)
+
+DEFAULT_CERT_TYPE = "pem"
 
 
 def load_pem_x509_certificate(data):
     """Load X.509 PEM certificate."""
-    return _x509.load_pem_x509_certificate(data, _backends.default_backend())
+    return _x509.load_pem_x509_certificate(data)
+
+
+def load_der_x509_certificate(data):
+    """Load X.509 DER certificate."""
+    return _x509.load_der_x509_certificate(data)
+
+
+def load_x509_certificate(data, cert_type="pem"):
+    cert_reader = _x509_loaders.get(cert_type)
+
+    if not cert_reader:
+        cert_reader = _x509_loaders.get("pem")
+        context = {
+            "message": "Unknown cert_type, falling back to default",
+            "cert_type": cert_type,
+            "default": DEFAULT_CERT_TYPE,
+        }
+        logger.warning(context)
+
+    cert = cert_reader(data)
+    return cert
+
+
+def get_public_bytes_from_cert(cert):
+    data = cert.public_bytes(_cryptography_encoding.PEM).decode()
+    return data
+
+
+_x509_loaders = {
+    "pem": load_pem_x509_certificate,
+    "der": load_der_x509_certificate,
+}